Polyanhydride modified adducts or reactants and oleaginous compositions containing same

ABSTRACT

An oil soluble dispersant additive useful in oleaginous compositions selected from fuels and lubricating oils comprising the reaction products of: 
     (i) at least one intermediate adduct comprised of the reaction products of 
     (a) at least one polyanhydride, and 
     (b) at least one member selected from the group consisting of polyamines, polyols, and amino alcohols; and 
     (ii) at least one member selected from the group consisting of 
     (a) at least one long chain hydrocarbyl substituted C 4  -C 10  dicarboxylic acid producing material, or 
     (b) at least one long chain hydrocarbyl substituted hydroxy aromatic material and at least one aldehyde. 
     Also disclosed are oleaginous compositions, particularly lubricating oil compositions, containing these oil soluble dispersants.

This is a continuation of application Ser. No. 161,919, filed Feb. 29,1988, now abandoned.

FIELD OF THE INVENTION

This invention relates to oil soluble dispersant additives useful inoleaginous compositions selected from fuel and lubricating oilcompositions, including concentrates containing said additives, andmethods for their manufacture and use. The dispersant additives arepolyanhydride adducts which have been prepared by first reacting apolyanhydride with a polyamine, a polyol or an amino alcohol to form anintermediate adduct, whereafter the intermediate adduct is reacted with(1) a long chain hydrocarbon substituted hydroxy aromatic material suchas phenol and an aldehyde such as formaldehyde or (2) a dicarboxylicacid, anhydride, ester, etc. which in turn has been substituted with ahigh molecular weight hydrocarbon group. The high molecular weighthydrocarbon group has a number average molecular weight (M_(n)) of about500 to about 6,000. The additives will have a ratio (functionality) ofabout 0.7 to 2.0 dicarboxylic acid producing moieties for eachequivalent weight of the high molecular weight hydrocarbon therein.

BACKGROUND OF THE INVENTION

Multigrade lubricating oils typically are identified by two numbers suchas 10W30, 5W30 etc. The first number in the multigrade designation isassociated with a maximum low temperature (e.g.-20° C.) viscosityrequirement for that multigrade oil as measured typically by a coldcranking simulator (CCS) under high shear, while the second number inthe multigrade designation is associated with a minimum high temperature(e.g. 100° C.) viscosity requirement. Thus, each particular multigradeoil must simultaneously meet both strict low and high temperatureviscosity requirements in order to qualify for a given multigrade oildesignation. Such requirements are set e.g., by ASTM specifications. By"low temperature" as used herein is meant temperatures of typically fromabout -30° to about -5° C. By "high temperature" as used herein is meanttemperatures of typically at least about 100° C.

The minimum high temperature viscosity requirement, e.g. at 100° C., isintended to prevent the oil from thinning out too much during engineoperation which can lead to excessive wear and increased oilconsumption. The maximum low temperature viscosity requirement isintended to facilitate engine starting in cold weather and to ensurepumpability, i.e., the cold oil should readily flow or slump into thewell for the oil pump, otherwise the engine can be damaged due toinsufficient lubrication.

In formulating an oil which efficiently meets both low and hightemperature viscosity requirements, the formulator may use a single oilof desired viscosity or a blend of two lubricating oils of differentviscosities, in conjunction with manipulating the identity and amount ofadditives that must be present to achieve the overall target propertiesof a particular multigrade oil including its viscosity requirements.

The natural viscosity characteristic of a lubricating oil is typicallyexpressed by the neutral number of the oil (e.g. S150N) with a higherneutral number being associated with a higher natural viscosity at agiven temperature. In some instances the formulator will find itdesirable to blend oils of two different neutral numbers, and henceviscosities, to achieve an oil having a viscosity intermediate betweenthe viscosity of the components of the oil blend. Thus, the neutralnumber designation provides the formulator with a simple way to achievea desired base oil of predictable viscosity. Unfortunately, merelyblending oils of different viscosity characteristics does not enable theformulator to meet the low and high temperature viscosity requirementsof multigrade oils. The formulator's primary tool for achieving thisgoal is an additive conventionally referred to as a viscosity indeximprover (i.e., V.I. improver).

The V.I. improver is conventionally an oil-soluble long chain polymer.The large size of these polymers enables them to significantly increaseKinematic viscosities of base oils even at low concentrations. However,because solutions of high polymers are non-Newtonian they tend to givelower viscosities than expected in a high shear environment due to thealignment of the polymer. Consequently, V.I. improvers impact (i.e.,increase) the low temperature (high shear) viscosities (i.e. CCSviscosity) of the base oil to a lesser extent than they do the hightemperature (low shear) viscosities.

The aforesaid viscosity requirements for a multigrade oil can thereforebe viewed as being increasingly antagonistic at increasingly higherlevels of V.I. improver. For example, if a large quantity of V.I.improver is used in order to obtain high viscosity at high temperatures,the oil may now exceed the low temperature requirement. In anotherexample, the formulator may be able to readily meet the requirement fora 10W30 oil but not a 5W30 oil, with a particular ad-pack (additivepackage) and base oil. Under these circumstances the formulator mayattempt to lower the viscosity of the base oil, such as by increasingthe proportion of low viscosity oil in a blend, to compensate for thelow temperature viscosity increase induced by the V.I. improver, inorder to meet the desired low and high temperature viscosityrequirements. However, increasing the proportion of low viscosity oilsin a blend can in turn lead to a new set of limitations on theformulator, as lower viscosity base oils are considerably less desirablein diesel engine use than the heavier, more viscous oils.

Further complicating the formulator's task is the effect that dispersantadditives can have on the viscosity characteristics of multigrade oils.Dispersants are frequently present in quality oils such as multigradeoils, together with the V.I. improver. The primary function of adispersant is to maintain oil insolubles, resulting from oxidationduring use, in suspension in the oil thus preventing sludge flocculationand precipitation. Consequently, the amount of dispersant employed isdictated and controlled by the effectiveness of the material forachieving its dispersant function. A high quality 10W30 commercial oilmight contain from two to four times as much dispersant as V.I. improver(as measured by the respective dispersant and V.I. improver activeingredients). In addition to dispersancy, conventional dispersants canalso increase the low and high temperature viscosity characteristics ofa base oil simply by virtue of their polymeric nature. In contrast tothe V.I. improver, the dispersant molecule is much smaller.Consequently, the dispersant is much less shear sensitive, therebycontributing more to the low temperature CCS viscosity (relative to itscontribution to the high temperature viscosity of the base oil) than aV.I. improver. Moreover, the smaller dispersant molecule contributesmuch less to the high temperature viscosity of the base oil than theV.I. improver. Thus, the magnitude of the low temperature viscosityincrease induced by the dispersant can exceed the low temperatureviscosity increase induced by the V.I. improver without the benefit of aproportionately greater increase in high temperature viscosity asobtained from a V.I. improver. Consequently, as the dispersant inducedlow temperature viscosity increase causes the low temperature viscosityof the oil to approach the maximum low temperature viscosity limit, themore difficult it is to introduce a sufficient amount of V.I. improvereffective to meet the high temperature viscosity requirement and stillmeet the low temperature viscosity requirement. The formulator isthereby once again forced to shift to the undesirable expedient of usinghigher proportions of low viscosity oil to permit addition of therequisite amount of V.I. improver without exceeding the low temperatureviscosity limit.

In accordance with the present invention, dispersants are provided whichpossess inherent characteristics such that they contribute considerablyless to low temperature viscosity increases than dispersants of theprior art while achieving similar or greater high temperature viscosityincreases. Moreover, as the concentration of dispersant in the base oilis increased, this beneficial low temperature viscosity effect becomesincreasingly more pronounced relative to conventional dispersants. Thisadvantage is especially significant for high quality heavy duty dieseloils which typically require high concentrations of dispersant additive.Furthermore, these improved viscosity properties facilitate the use ofV.I. improvers in forming multigrade oils spanning a wider viscosityrequirement range, such as 5W30 oils, due to the overall effect of lowerviscosity increase at low temperatures while maintaining the desiredviscosity at high temperatures as compared to the other dispersants.More significantly, these viscometric properties also permit the use ofhigher viscosity base stocks with attendant advantages in engineperformance. Furthermore, the utilization of the dispersant additives ofthe instant invention allows a reduction in the amount of V.I. improversrequired.

The materials of this invention are thus an improvement overconventional dispersants because of their effectiveness as dispersantscoupled with enhanced low temperature viscometric properties. Thesematerials are particularly useful with V.I. improvers in formulatingmultigrade oils.

SUMMARY OF THE INVENTION

The present invention is directed to oil soluble dispersant additivesuseful in oleaginous compositions selected from fuels and lubricatingoils comprising the reaction products of:

(i) at least one intermediate adduct comprised of the reaction productsof

(a) at least one polyanhydride, and

(b) at least one member selected from the group consisting ofpolyamines, polyols, and amino alcohols; and

(ii) at least one member selected from the group consisting of

(a) long chain hydrocarbon substituted C₄ -C₁₀ dicarboxylic acidproducing material, or

(b) long chain hydrocarbon substituted hydroxy aromatic material and analdehyde.

The intermediate adduct (i) is first preformed and this preformedintermediate adduct is subsequently reacted with (ii).

DETAILED DESCRIPTION OF THE INVENTION

In accordance with the present invention there are provided oil solubledispersant compositions. These dispersants exhibit a high temperature tolow temperature viscosity balance or ratio which is more favorable thanthat of conventional dispersant materials. That is to say the instantdispersant materials possess inherent characteristics such that theycontribute less to low temperature viscosity increase than conventionalprior art dispersants while increasing the contribution to the hightemperature viscosity increase.

The dispersant materials of the instant invention comprise the reactionproducts of

(i) at least one intermediate adduct comprised of the reaction productsof

(a) at least one polyanhydride, and

(b) at least one member selected from the group consisting ofpolyamines, polyols, and amino alcohols; and

(ii) at least one member selected from the group consisting of

(a) long chain hydrocarbon substituted C₄ -C₁₀ dicarboxylic acidproducing material, or

(b) long chain hydrocarbon substituted hydroxy aromatic material and analdehyde.

The reaction product (i), also referred to in the specification andappended claims as the intermediate adduct, is then reacted with either(ii)(a) or (ii)(b) to form the adduct or dispersant of the presentinvention. If (i)(b) is a polyamine then it contains at least tworeactive amino groups, one of said amino groups being a primary aminogroup and the other reactive amino group being a primary amino group ora secondary amino group.

In a preferred embodiment of the instant invention (i)(b) is apolyamine, and in the following discussion concerning the reactionbetween (i)(a) and (i)(b) to form the intermediate adduct, (i)(b) willbe assumed to be such a polyamine.

For purposes of illustration and exemplification only the reactionbetween one mole of a polyanhydride, e.g., a dianhydride, and two molesof a polyamine such as tetraethylene pentamine (TEPA) to form theintermediate adduct is believed to be represented by the followingreaction scheme: ##STR1##

This intermediate adduct is then reacted with either (ii)(a) or (ii)(b)to form the dispersant of this invention. For purpose of illustrationand exemplification only if this intermediate adduct is reacted with(ii)(a), such as polyisobutenyl succinic anhydride, i.e., 2 moles of##STR2## where PIB represents polyisobutylene having a number averagemolecular weight of from about 500 to about 6,000, the product is amixture of amides, imides and esters, e.g., ##STR3## Product A is animide formed by the reaction of both moles of polyisobutenyl succinicanhydride (ii)(a) with the primary amino groups of the intermediateadduct. Product B is an imide-amide formed by the reaction of one moleof polyisobutenyl succinic anhydride (ii)(a) with a primary amino groupof the intermediate adduct and the reaction of the second mole of(ii)(a) with a secondary amino group of the intermediate adduct. ProductC is formed by the reaction of both moles of (ii)(a) with secondaryamino groups of the intermediate adduct (i).

If the intermediate adduct is reacted with (ii)(b) the reaction may berepresented as follows: ##STR4##

ACID PRODUCING MATERIAL

The long chain hydrocarbon substituted C₄ -C₁₀ dicarboxylic acidproducing materials or acylating agents which may be reacted with thepolyanhydride-polyamine, polyanhydride-polyol, and/orpolyanhydride-amino alcohol intermediate adducts to form the dispersantadditives of the instant invention are dicarboxylic acid materials,e.g., acid, anhydride or ester materials, which are substituted with along chain hydrocarbyl group, generally a polyolefin, and which containtypically an average of at least about 0.7, usefully from about 0.7-2.0(e.g., 0.9-1.6) preferably about 1.0-1.3 (e.g. 1.1-1.2) moles, per moleof hydrocarbyl, of a C₄ to C₁₀ dicarboxylic acid, anhydride or esterthereof, such as succinic acid, succinic anhydride, dimethylmethylsuccinate, etc., and mixtures thereof.

The hydrocarbyl substituted dicarboxylic acid materials, as well asmethods for their preparation, are well known in the art and are amplydescribed in the patent literature. They may be obtained, for example,by the Ene reaction between a polyolefin and an alpha-beta unsaturatedC₄ to C₁₀ dicarboxylic acid, anhydride or ester thereof, such as fumaricacid, itaconic acid, maleic acid, maleic anhydride, chloromaleic acid,dimethyl fumarate, etc.

The hydrocarbyl substituted dicarboxylic acid materials function asacylating agents for the polyepoxide intermediate adduct.

Preferred olefin polymers for reaction with the unsaturated dicarboxylicacid, anhydride, or ester are polymers comprising a major molar amountof C₂ to C₈, e.g. C₂ to C₅, monoolefin. Such olefins include ethylene,propylene, butylene, isobutylene, pentene, octene-1, styrene, etc. Thepolymers can be homopolymers such as polyisobutylene, as well ascopolymers of two or more of such olefins such as copolymers of:ethylene and propylene; butylene and isobutylene; propylene andisobutylene; etc. Other copolymers include those in which a minor molaramount of the copolymer monomers, e.g., 1 to 10 mole %, is a C₄ to C₁₈non-conjugated diolefin, e.g., a copolymer of isobutylene and butadiene;or a copolymer of ethylene, propylene and 1,4-hexadiene; etc.

In some cases the olefin polymer may be completely saturated, forexample an ethylene-propylene copolymer made by a Ziegler-Nattasynthesis using hydrogen as a moderator to control molecular weight.

The olefin polymers will usually have number average molecular weights(M_(n)) within the range of about 500 and about 6000, e.g. 700 to 3000,preferably between about 800 and about 2500. An especially usefulstarting material for a highly potent dispersant additive made inaccordance with this invention is polyisobutylene.

Processes for reacting the olefin polymer with the C₄ -C₁₀ unsaturateddicarboxylic acid, anhydride or ester are known in the art. For example,the olefin polymer and the dicarboxylic acid material may be simplyheated together as disclosed in U.S. Pat. Nos. 3,361,673 and 3,401,118to cause a thermal "ene" reaction to take place. Alternatively, theolefin polymer can be first halogenated, for example, chlorinated orbrominated to about 1 to 8 wt. %, preferably 3 to 7 wt. % chlorine orbromine, based on the weight of polymer, by passing the chlorine orbromine through the polyolefin at a temperature of 25° to 160° C., e.g.,120° C., for about 0.5 to 10, preferably 1 to 7 hours. The halogenatedpolymer may then be reacted with sufficient unsaturated acid oranhydride at 100° to 250° C., usually about 180° to 220 ° C., for about0.5 to 10 hours, e.g. 3 to 8 hours, so the product obtained will containan average of about 1.0 to 2.0 moles, preferably 1.1 to 1.4 moles, e.g.,1.2 moles, of the unsaturated acid per mole of the halogenated polymer.Processes of this general type are taught in U.S. Pat. Nos. 3,087,436;3,172,892; 3,272,746 and others.

Alternatively, the olefin polymer and the unsaturated acid material aremixed and heated while adding chlorine to the hot material. Processes ofthis type are disclosed in U.S. Pat. Nos. 3,215,707; 3,231,587;3,912,764; 4,110,349; 4,234,435; and in U.K. 1,440,219.

By the use of halogen, about 65 to 95 wt. % of the polyolefin, e.g.polyisobutylene, will normally react with the dicarboxylic acidmaterial. Upon carrying out a thermal reaction without the use ofhalogen or a catalyst, then usually only about 50 to 85 wt. % of thepolyisobutylene will react. Chlorination helps increase the reactivity.For convenience, all of the aforesaid functionality ratios ofdicarboxylic acid producing units to polyolefin, e.g. 1.0 to 2.0, etc.are based upon the total amount of polyolefin, that is, the total ofboth the reacted and unreacted polyolefin, present in the resultingproduct formed in the aforesaid reactions.

THE LONG CHAIN HYDROCARBON SUBSTITUTED HYDROXY AROMATIC MATERIAL

The hydrocarbyl substituted hydroxy aromatic compounds used in theinvention include those compounds having the formula ##STR5## wherein Arrepresents ##STR6## wherein a is 1 or 2, R¹¹ is a long chain hydrocarbonR¹⁰ is a hydrocarbon or substituted hydrocarbon radical, having from 1to about 3 carbon atoms or a halogen radical such as the bromide orchloride radical, f is an integer from 1 to 2, c is an integer from 0 to2, and d is an integer from 1 to 2.

Illustrative of such Ar groups are phenylene, biphenylene, naphthyleneand the like.

The preferred long chain hydrocarbon substituents are olefin polymerscomprising a major molar amount of C₂ to C₁₀, e.g. C₂ to C₅ monoolefin.Such olefins include ethylene, propylene, butylene, pentene, octene-1,styrene, etc. The polymers can be homopolymers such as polyisobutylene,as well as copolymers of two or more of such olefins such as copolymersof: ethylene and propylene; butylene and isobutylene; propylene andisobutylene; etc. Other copolymers include those in which a minor molaramount of the copolymer monomers, e.g., a copolymer of isobutylene andbutadiene; or a copolymer of ethylene, propylene and 1,4-hexadiene; etc.

In some cases, the olefin polymer may be completely saturated, forexample an ethylene-propylene copolymer made by a Ziegler-Nattasynthesis using hydrogen as a moderator to control molecular weight.

The olefin polymers will usually have a number average molecular weight(M_(n)) within the range of about 500 and about 7,000, more usuallybetween about 700 and about 3,000. Particularly useful olefin polymershave a number average molecular weight within the range of about 800 toabout 2500, and more preferably within the range of about 850 to about1,000 with approximately one terminal double bond per polymer chain. Anespecially useful starting material for a highly potent dispersantadditive made in accordance with this invention is polyisobutylene. Thenumber average molecular weight for such polymers can be determined byseveral known techniques. A convenient method for such determination isby gel permeation chromatography (GPC) which additionally providesmolecular weight distribution information, see W. W. Yau, J. J. Kirklandand D. D. Bly, "Modern Size Exclusion Liquid Chromatography", John Wileyand Sons, New York, 1979.

Processes for substituting the hydroxy aromatic compounds with theolefin polymer are known in the art and may be depicted as follows:##STR7## where R¹⁰, R¹¹, f and c are as previously defined, and BF₃ isan alkylating catalyst. Processes of this type are described, forexample, in U.S. Pat. Nos. 3,539,633 and 3,649,229, the disclosures ofwhich are incorporated herein by reference.

Representative hydrocarbyl substituted hydroxy aromatic compoundscontemplated for use in the present invention include, but are notlimited to, 2-polypropylene phenol, 3-polypropylene phenol,4-polypropylene phenol, 2-polybutylene phenol, 3-polyisobutylene phenol,4-polyisobutylene phenol, 4-polyisobutylene-2-chlorophenol,4-polyisobutylene-2-methylphenol, and the like.

Suitable hydrocarbyl-substituted polyhydroxy aromatic compounds includethe polyolefin catechols, the polyolefin resorcinols, and the polyolefinhydroquinones, e.g., 4-polyisobutylene-1,2-dihydroxybenzene,3-polypropylene-1,2-dihydroxy-benzene,5-polyisobutylene-1,3-dihydroxybenzen,4-polyamylene-1,3-dihydroxybenzene, and the like.

Suitable hydrocarbyl-substituted naphthols include1-polyisobutylene-5-hydroxynaphthalene,1-polypropylene-3-hydroxynaphthalene and the like.

The preferred long chain hydrocarbyl substituted hydroxy aromaticcompounds to be used in this invention can be illustrated by theformula: ##STR8## wherein R¹² is hydrocarbyl of from 50 to 300 carbonatoms, and preferably is a polyolefin derived from a C₂ to C₁₀ (e.g., C₂and C₅) mono-alpha-olefin.

THE ALDEHYDE MATERIAL

The aldehyde material which can be employed in this invention isrepresented by the formula:

    R.sup.13 CHO

in which R¹³ is a hydrogen or an aliphatic hydrocarbon radical havingfrom 1 to 4 carbon atoms. Examples of suitable aldehydes includeformaldehyde, paraformaldehyde, acetaldehyde and the like.

POLYAMINES

Amine compounds useful as reactants with the polyanhydride to form thepolyanhydride-polyamine intermediate adduct are those containing atleast two reactive amino groups, i.e., primary and secondary aminogroups. They include polyalkylene polyamines, of about 2 to 60 (e.g. 2to 30) , preferably 2 to 40, (e.g. 3 to 20) total carbon atoms and about1 to 12 (e.g., 2 to 9), preferably 3 to 12, and most preferably 3 to 9nitrogen atoms in the molecule. These amines may be hydrocarbyl aminesor may be hydrocarbyl amines including other groups, e.g, hydroxygroups, alkoxy groups, amide groups, nitriles, imidazoline groups, andthe like. Hydroxy amines with 1 to 6 hydroxy groups, preferably 1 to 3hydroxy groups are particularly useful. Such amines should be capable ofreacting with the acid or anhydride groups of the hydrocarbylsubstituted dicarboxylic acid moiety and with the anhydride groups ofthe polyanhydride moiety through the amino functionality or asubstituent group reactive functionality. Since tertiary amines aregenerally unreactive with anhydrides it is desirable to have at leasttwo primary and/or secondary amino groups on the amine. It is preferredthat the amine contain at least one primary amino group, for reactionwith the polyanhydride, and at least one secondary amino group, forreaction with the acylating agent. Preferred amines are aliphaticsaturated amines, including those of the general formulae: ##STR9##wherein R^(IV), R', R'' and R''' are independently selected from thegroup consisting of hydrogen; C₁ to C₂₅ straight or branched chain alkylradicals; C₁ to C₁₂ alkoxy C₂ to C₆ alkylene radicals; C₂ to C₁₂ hydroxyamino alkylene radicals; and C₁ to C₁₂ alkylamino C₂ to C₆ alkyleneradicals; and wherein R''' can additionally comprise a moiety of theformula ##STR10## wherein R' is as defined above, and wherein each s ands' can be the same or a different number of from 2 to 6, preferably 2 to4; and t and t' can be the same or different and are each numbers oftypically from 0 to 10, preferably about 2 to 7, most preferably about 3to 7, with the proviso that t+t' is not greater than 10. To assure afacile reaction it is preferred that R^(IV), R', R'', R''', (s), (s'),(t) and (t') be selected in a manner sufficient to provide the compoundsof formula Ia with typically at least two primary and/or secondary aminogroups. This can be achieved by selecting at least one of said R^(IV),R', R", or R''' groups to be hydrogen or by letting (t) in formula Ia beat least one when R''' is H or when the (Ib) moiety possesses asecondary amino group. The most preferred amines of the above formulasare represented by formula Ia and contain at least two primary aminogroups and at least one, and preferably at least three, secondary aminogroups.

Non-limiting examples of suitable amine compounds include:1,2-diaminoethane; 1,3-diaminopropane; 1,4-diaminobutane;1,6-diaminohexane; polyethylene amines such as diethylene triamine;triethylene tetramine; tetraethylene pentamine; polypropylene aminessuch as 1,2-propylene diamine; di-(1,2-propylene) triamine;di-(1,3-propylene) triamine; N,N-dimethyl-1, 3-diaminopropane;N,N-di-(2-aminoethyl) ethylene diamine: N-dodecyl-1,3-propane diamine;diisopropanol amine; mono-, di-, and tri-tallow amines; aminomorpholines such as N-(3-aminopropyl) morpholine; and mixtures thereof.

Other useful amine compounds include: alicyclic diamines such as1,4-di(aminoethyl) cyclohexane, and N-aminoalkyl piperazines of thegeneral formula: ##STR11## wherein p₁ and p₂ are the same or differentand are each integers of from 1 to 4, and n₁, n₂ and n₃ are the same ordifferent and are each integers of from 1 to 3.

Commercial mixtures of amine compounds may advantageously be used. Forexample, one process for preparing alkylene amines involves the reactionof an alkylene dihalide (such as ethylene dichloride or propylenedichloride) with ammonia, which results in a complex mixture of alkyleneamines wherein pairs of nitrogens are joined by alkylene groups, formingsuch compounds as diethylene triamine, triethylenetetramine,tetraethylene pentamine and corresponding piperazines. Low costpoly(ethyleneamine) compounds averaging about 5 to 7 nitrogen atoms permolecule are available commercially under trade names such as "PolyamineH", "Polyamine 400", "Dow Polyamine E-100", etc.

Useful amines also include polyoxyalkylene polyamines such as those ofthe formulae: ##STR12## where m has a value of about 3 to 70 andpreferably 10 to 35; and ##STR13## where n has a value of about 1 to 40,with the provision that the sum of all the n's is from about 3 to about70, and preferably from about 6 to about 35, and R^(V) is a substitutedsaturated hydrocarbon radical of up to 10 carbon atoms, wherein thenumber of substituents on the R^(V) group is from 3 to 6, and "a" is anumber from 3 to 6 which represents the number of substituents on R^(V).The alkylene groups in either formula (III) or (IV) may be straight orbranch®d chains containing about 2 to 7, and preferably about 2 to 4carbon atoms.

The polyoxyalkylene polyamines of formulas (III) or (IV) above,preferably polyoxyalkylene diamines and polyoxyalkylene triamines, mayhave number average molecular weights ranging from about 200 to about4000 and preferably from about 400 to about 2000. The preferredpolyoxyalkylene polyamines include the polyoxyethylene andpolyoxypropylene diamines and the polyoxypropylene triamines havingaverage molecular weights ranging from about 200 to 2000. Thepolyoxyalkylene polyamines are commercially available and may beobtained, for example, from the Jefferson Chemical Company, Inc. underthe trade name "Jeffamines D-230, D-400, D-1000, D-2000, T-403", etc.

The polyamine is readily reacted with the polyanhydride, with or withouta catalyst, simply by heating a mixture of the polyanhydride andpolyamine in a reaction vessel at a temperature of about 30° C. to about200° C., more preferably to a temperature of about 75° C. to about 180°C., and most preferably at about 90° C. to about 160° C., for asufficient period of time to effect reaction. A solvent for thepolyanhydride, polyamine and/or intermediate adduct can be employed tocontrol viscosity and/or reaction rates.

Catalysts useful in the promotion of the above-identifiedpolyanhydride-polyamine reactions are selected from the group consistingof stannous octanoate, stannous hexanoate, stannous oxalate, tetrabutyltitanate, a variety of metal organic based catalyst acid catalysts andamine catalysts, as described on page 266, and forward in a book chapterauthorized by R. D. Lundberg and E. F. Cox entitled, "Kinetics andMechanisms of Polymerization: Ring Opening Polymerization", edited byFrisch and Reegen, published by Marcel Dekker in 1969, wherein stannousoctanoate is an especially preferred catalyst. The catalyst is added tothe reaction mixture at a concentration level of about 50 to about10,000 parts of catalyst per one million parts by weight of the totalreaction mixture.

POLYOL

In another aspect of the invention the polyanhydride intermediateadducts are prepared by reacting the polyanhydride with a polyol insteadof with a polyamine.

Suitable polyol compounds which can be used include aliphatic polyhydricalcohols containing up to about 100 carbon atoms and about 2 to about 10hydroxyl groups. These alcohols can be quite diverse in structure andchemical composition, for example, they can be substituted orunsubstituted, hindered or unhindered, branched chain or straight chain,etc. as desired. Typical alcohols are alkylene glycols such as ethyleneglycol, propylene glycol, trimethylene glycol, butylene glycol, andpolyglycol such as diethylene glycol, triethylene glycol, tetraethyleneglycol, dipropylene glycol, tripropylene glycol, dibutylene glycol,tributylene glycol, and other alkylene glycols and polyalkylene glycolsin which the alkylene radical contains from two to about eight carbonatoms. Other useful polyhydric alcohols include glycerol, monomethylether of glycerol, pentaerythritol, dipentaerythritol,tripentaerythritol, 9,10-dihydroxystearic acid, the ethyl ester of9,10-dihydroxystearic acid, 3-chloro-1,2propanediol, 1,2-butanediol,1,4-butanediol, 2,3-hexanediol, pinacol, tetrahydroxy pentane,erythritol, arabitol, sorbitol, mannitol, 1,2-cyclohexanediol,1,4-cyclohexanediol, 1,4-(2-hydroxyethyl)-cyclohexane,1,4-dihydroxy-2-nitrobutane, 1,4-di-(2-hydroxyethyl)benzene, thecarbohydrates such as glucose, mannose, glyceraldehyde, and galactose,and the like, copolymers of allyl alcohol and styrene,N,N'-di-(2-hydroxylethyl) glycine and esters thereof with lower mono-andpolyhydric aliphatic alcohols, etc.

Included within the group of aliphatic alcohols are those alkane polyolswhich contain ether groups such as polyethylene oxide repeating units,as well as those polyhydric alcohols containing at least three hydroxylgroups, at least one of which has been esterified with a mono-carboxylicacid having from eight to about 30 carbon atoms such as octanoic acid,oleic acid, stearic acid, linoleic acid, dodecanoic acid, or tall oilacid. Examples of such partially esterified polyhydric alcohols are themono-oleate of sorbitol, the mono-oleate of glycerol, the monostearateof glycerol, the di-stearate of sorbitol, and the di-dodecanoate oferythritol.

A preferred class of intermediates are those prepared from aliphaticalcohols containing up to 20 carbon atoms, and especially thosecontaining three to 15 carbon atoms. This class of alcohols includesglycerol, erythritol, pentaerythritol, dipentaerythritol,tripentaerythritol, gluconic acid, glyceraldehyde, glucose, arabinose,1,7-heptanediol, 2,4-heptanediol, 1,2,3-hexanetriol, 1,2,4-hexanetriol,1,2,5-hexanetriol, 2,3,4-hexanetriol, 1,2,3-butanetriol,1,2,4-butanetriol, quinic acid,2,2,6,6-tetrakis(hydroxymethyl)-cyclohexanol, 1,10-decanediol,digitalose, and the like. The adducts prepared from aliphatic alcoholscontaining at least three hydroxyl groups and up to fifteen carbon atomsare particularly preferred.

An especially preferred class of polyhydric alcohols for preparing thepolyanhydride adducts used as intermediate materials or dispersantprecursors in the present invention are the polyhydric alkanolscontaining three to 15, especially three to six carbon atoms and havingat least three hydroxyl groups. Such alcohols are exemplified in theabove specifically identified alcohols and are represented by glycerol,erythritol, pentaerythritol, mannitol, sorbitol, 1,2,4-hexanetriol, andtetrahydroxy pentane and the like.

The polyol is readily reacted with the polyanhydride by heating amixture of the polyol and polyanhydride in a reaction vessel at atemperature of about 50° C. to about 200° C., more preferably to atemperature of about 75° C. to about 180° C., and most preferable atabout 90° C. to about 160° C., for a sufficient period of time to effectreaction. Optionally, a solvent for the polyanhydride, polyol and/or theresulting adduct may be employed to control viscosity and/or thereaction rates.

Catalysts useful in the promotion of the polyanhydride-polyol reactionsare the same as those which are useful in connection with thepolyanhydride-polyamine reactions discussed above. The catalyst may beadded to the reaction mixture at a concentration level of from about 50to about 10,000 parts of catalyst per one million parts by weight oftotal reaction mixture.

AMINO ALCOHOL

In a manner analogous to that described for the polyanhydride-polyaminereaction and for the polyanhydride-polyol reaction, the polyanhydridecan be reacted with an amino alcohol to form an intermediate adductwhich can be further reacted with an acylating agent to form thedispersants of this invention.

Suitable amino alcohol compounds which can be reacted with thepolyanhydride include those containing up to about 50 total carbon atomsand preferably up to about 10 total carbon atoms, from 1 to about 5nitrogen atoms, preferably from 1 to 3 nitrogen atoms, and from 1 toabout 15 hydroxyl groups, preferably from about 1 to 5 hydroxyl groups.Preferred amino alcohols include the2,2-disubstituted-2-amino-1-alkanols having from two to three hydroxygroups and containing a total of 4 to 8 carbon atoms. These aminoalcohols can be represented by the formula: ##STR14## wherein Z isindependently an alkyl or hydroxyalkyl group with the alkyl groupshaving from 1 to 3 carbon atoms wherein at least one, and preferablyboth, of the X substituents is a hydroxyalkyl group of the structure--(CH₂)_(n) OH, n being 1 to 3. Examples of such amino alcohols include:tri-(3-hydroxypropyl) amine; 2-amino-2-methyl-1,3-propanediol;2-amino-2-ethyl1,3-propanediol; and2-amino-2(hydroxymethyl)-1,3-propanediol; the latter also being known asTHAM or tris(hydroxymethyl) amino methane. THAM is particularlypreferred because of its effectiveness, availability and low cost.

The amino alcohol is readily reacted with the polyanhydride by heating amixture of the polyanhydride and amino alcohol in a reaction vessel at atemperature of about 50° C. to about 200° C., more preferably attemperature of about 75° C. to about 180° C., and most preferably atabout 90° C. to about 160° C., for a sufficient period of time to effectreaction. Optionally, a solvent for the polyanhydride, amino alcoholand/or the reaction product may be used to control viscosity and/or thereaction rates.

Catalysts useful in the promotion of the polyanhydride-amino alcoholreactions are the same as those which are useful in connection with thepolyanhydride-polyamine and polyanhydride-polyol reactions, andcorresponding amounts of catalysts may be employed.

POLYANHYDRIDES

The polyanhydrides which are reacted with the aforedescribed polyamines,polyols and/or amino alcohols to form the intermediate adducts ordispersant precursors of the instant invention are compounds containingat least two dicarboxylic acid anhydride moieties. These anhydridemoieties are connected or joined by polyvalent hydrocarbon moieties orhydrocarbon moieties containing at least one hetero atom or group. Thehydrocarbon moieties generally contain from 1 to about 1,000 carbonatoms, preferably from 2 to about 500 carbon atoms. These hydrocarbonmoieties may be aliphatic, either saturated aliphatic or unsaturatedaliphatic, cycloaliphatic, aromatic, or aliphatic aromatic. They may bemonomeric or polymeric, e.g., polyisobutylene, in character. Thealiphatic hydrocarbon moieties contain from 1 to about 1,000, preferably2 to about 500, carbon atoms. The cycloaliphatic hydrocarbon moietiescontain from 4 to about 16 ring carbon atoms. The ring carbon atoms maycontain substituent groups, e.g., alkyl groups such as C₁ -C₁₀ alkylgroups thereon. The aromatic hydrocarbon moieties contain from 6 toabout 20 ring carbon atoms. The aliphatic-aromatic moieties contain from7 to about 100, preferably 7 to about 50, carbon atoms. The hydrocarbonmoieties joining the anhydride groups may contain substituent groupsthereon. The substituent groups are those which are substantially inertor unreactive at ambient conditions with the anhydride groups. As usedin the specification and appended claims the term "substantially inertand unreactive at ambient conditions" is intended to mean that the atomor group is substantially inert to chemical reactions at ambienttemperature and pressure with the anhydride group so as not tomaterially interfere in an adverse manner with the preparation and/orfunctioning of the compositions, additives, compounds, etc. of thisinvention in the context of its intended use. For example, small amountsof these atoms or groups can undergo minimal reaction with the anhydridegroup without preventing the making and using of the invention asdescribed herein. In other words, such reaction, while technicallydiscernable, would not be sufficient to deter the practical worker ofordinary skill in the art from making and using the invention for itsintended purposes. Suitable substituent groups include, but are notlimited to, alkyl groups, hydroxyl groups, tertiary amino groups,halogens, and the like. When more than one substituent is present theymay be the same or different.

It is to be understood that while many substituent groups aresubstantially inert or unreactive at ambient conditions with theanhydride group they will react with the anhydride group underconditions effective to allow reaction of the anhydride group with thereactive amino groups of the polyamine. Whether these groups aresuitable substituent groups which can be present on the polyanhydridedepends, in part, upon their reactivity with the anhydride group.Generally, if they are substantially more reactive with the anhydridegroup than the anhydride group is with the reactive amino group, theywill tend to materially interfere in an adverse manner with thepreparation of the dispersants of the present invention and may bepresent on the polyanhydride. An example of such a reactive but suitablegroup is the hydroxyl group. An example of an unsuitable substituentgroup is a primary amino group.

The hydrocarbon moieties containing at least one hetero atom or groupare the hydrocarbon moieties described above which contain at least onehetero atom or group in the chain. The hetero atom or groups are thosethat are substantially unreactive at ambient conditions with the oxiranerings. When more then one hetero atom or group is present they may bethe same or different. The hetero atoms or groups are preferablyseparated from the anhydride groups by at least one intervening carbonatom. These hetero atom or group containing hydrocarbon moieties maycontain at least one substituent group on at least one carbon atom.These substituent groups are the same as those described above as beingsuitable for the hydrocarbon moieties.

Some illustrative non-limiting examples of suitable hetero atoms orgroups include: ##STR15##

It is critical to the present invention that the polyanhydrides containat least two dicarboxylic acid anhydride moieties on the same molecule.These polyanhydrides may be further characterized as polyanhydridescontaining at least two dicarboxylic acid anhydride moieties joined orconnected by a hydrocarbon moiety, a substituted hydrocarbon moiety, ahydrocarbon moiety containing at least one hetero atom or group, or asubstituted hydrocarbon moiety containing at least one hetero atom orgroup. These polyanhydrides are well known in the art and are generallycommercially available or may be readily prepared by conventional andwell known methods.

The polyanhydrides of the instant invention may be represented by theformula ##STR16## wherein: b is 0 or 1;

w is the number of ##STR17## groups present on R, and is at least 2; Xis a q valent aliphatic acyclic hydrocarbon or substituted hydrocarbonradical containing from 2 to about 8 carbon atoms which together withthe two carbonyl carbon atoms forms a cyclic structure, where q is 3 or4; and

R is a z valent hydrocarbon radical, substituted hydrocarbon radical,hydrocarbon radical containing at least one hetero atom or group, orsubstituted hydrocarbon radical containing at least one hetero atom orgroup, where z=(q-2)w with the proviso that if b=0 then q=4.

In Formula V, X is independently selected from aliphatic, preferablysaturated, acylic trivalent or tetravalent hydrocarbon radicals orsubstituted hydrocarbon radicals containing from 2 to about 8 carbonatoms which together with the two carbonyl carbon atoms forms a mono- ordivalent cyclic structure. By trivalent or tetravalent hydrocarbonradicals is meant an aliphatic acyclic hydrocarbon, e.g., alkane, whichhas had removed from its carbon atoms three or four hydrogen atomsrespectively. Some illustrative non-limiting examples of these tri- andtetravalent aliphatic acyclic hydrocarbon radicals include: ##STR18##Since two of these valence bonds will be taken up by the two carbonylcarbon atoms there will be left one, in the case of x being trivalent,or two, in the case of x being tetravelent, valence bonds. Thus, if x isa trivalent radical the resulting cyclic structure formed between x andthe two carbonyl carbon atoms will be monovalent while if x is atetravalent radical the resulting cyclic structure will be divalent.

When X is a substituted aliphatic, preferably saturated, acyclic tri- ortetravalent hydrocarbon radical it contains from 1 to about 4substituent groups on one or more carbon atoms. If more than onesubstituent group is present they may be the same or different. Thesesubstituent groups are those that do not materially interfere in anadverse manner with the preparation and/or functioning of thecomposition, additives, compounds, etc. of this invention in the contextof its intended use. Some illustrative non-limiting examples of suitablesubstituent groups include alkyl radicals, preferably C₁ to C₅ alkylradicals; halogens, preferably chlorine and bromine, and hydroxylradicals. However, X is preferably unsubstituted.

When b is zero in Formula V the two carbonyl carbon atoms are bondeddirectly to the R moiety. An illustrative non-limiting example of such acase is cyclohexyl dianhydride; i.e., ##STR19##

In this cyclohexyl dianhydride R is a tetravalent cycloaliphatichydrocarbon radical, i.e., z=4, with q=4 since b is zero, and w=2.

In formula V w is an integer of at least 2. The upper limit of w is thenumber of replaceable hydrogen atoms present on R if p is one and x is atrivalent radical, or one half the number of replaceable hydrogen atomspresent on R if p is one and x is a tetravalent radical or if p is zero.Generally, however, w has an upper value not greater than about 10,preferably about 6, and more preferably about 4.

R in Formula V is selected from z valent hydrocarbon radicals,substituted z valent hydrocarbon radicals, z valent hydrocarbon radicalscontaining at least one hetero atom or group, and z valent substitutedhydrocarbon radicals containing at least one hetero atom or group. Thehydrocarbon radicals generally contain from 1 to about 1,000 carbonatoms, preferably from 2 to about 50 carbon atoms and may be aliphatic,either saturated or unsaturated, cycloaliphatic, aromatic, oraliphatic-aromatic. They may be saturated or unsaturated, e.g., containone or more ethylenic unsaturation sites. They may be polymeric ormonomeric. An example of a polymeric R is polyisobutylene containingfrom about 40 to about 500 carbon atoms.

The aliphatic hydrocarbon radicals represented by R are generally thosecontaining from 1 to about 1,000, preferably 2 to about 500, carbonatoms. They may be straight chain or branched. The cycloaliphaticradicals are preferably those containing from 4 to about 16 ring carbonatoms. They may contain substituent groups, e.g., lower alkyl groups, onone or more ring carbon atoms. These cycloaliphatic radicals include,for example, cycloalkylene, cycloalkylidine, cycloalkanetriyl, andcycloalkanetetrayl radicals. The aromatic radicals are typically thosecontaining from 6 to 12 ring carbon atoms.

It is to be understood that the term "aromatic" as used in thespecification and the appended claims is not intended to limit thepolyvalent aromatic moiety represented by R to a benzene nucleus.Accordingly it is to be understood that the aromatic moiety can be apyridine nucleus, a thiophene nucleus, a 1,2,3,4-tetrahydro naphthalenenucleus, etc., or a polynuclear aromatic moiety. Such polynuclearmoieties can be of the fused type; that is, wherein at least onearomatic nucleus is fused at two points to another nucleus such as foundin naphthalene, anthracene, the azanaphthalenes, etc. Alternatively,such polynuclear aromatic moieties can be of the linked type wherein atleast two nuclei (either mono- or polynuclear) are linked throughbridging linkages to each other. Such bridging linkages can be chosenfrom the group consisting of carbon-to-carbon single bonds, etherlinkages, keto linkages, sulfide linkages, polysulfide linkages of 2 to6 sulfur atoms, sulfinyl linkages, sulfonyl linkages, methylenelinkages, alkylene linkages, di-(lower alkyl)-methylene linkages, loweralkylene ether linkages, alkylene keto linkages, lower alkylene sulfurlinkages, lower alkylene polysulfide linkages of 2 to 6 carbon atoms,amino linkages, polyamino linkages and mixtures of such divalentbridging linkages.

When the aromatic moiety, Ar, is, for example, a divalent linkedpolynuclear aromatic moiety it can be represented by the general formula

    --Ar --(Lng--Ar)--.sub.w

wherein w is an integer of 1 to about 10, preferably 1 to about 8, morepreferably 1, 2 or 3; Ar is a divalent aromatic moiety as describedabove, and each Lng is a bridging linkage individually chosen from thegroup consisting of carbon-to-carbon single bonds, ether linkages (e.g.--O--), keto linkages (e.g., ##STR20## sulfide linkages (e.g., --S--),polysulfide linkages of 2 to 6 sulfur atoms (e.g., --S2--6--), sulfinyllinkages (e.g., --S(O)--), sulfonyl linkages (e.g., --S(O)2--), loweralkylene linkages ##STR21## di(lower alkyl) -methylene linkages (e.g.,--CR*₂ --), lower alkylene ether linkages (e.g., ##STR22## etc.) loweralkylene sulfide linkages (e.g., wherein one or more --O--'s in thelower alkylene ether linkages is replaced with an --S-- atom), loweralkylene polysulfide linkages (e.g., wherein one or more --O--'s isreplaced with a --S₂ --group), with R* being a lower alkyl group.

Illustrative of such divalent linked polynuclear aromatic moieties arethose represented by the formula ##STR23## wherein R¹² and R¹³ areindependently selected from hydrogen and alkyl radicals, preferablyalkyl radicals containing from 1 to about 20 carbon atoms; R¹¹ isselected from alkylene, alkylidene, cycloalkylene, and cycloalkylideneradicals; and u and u₁ are independently selected from integers having avalue of from 1 to 4.

The aliphatic-aromatic radicals are those containing from 7 to about 50carbon atoms.

Some illustrative non-limiting examples of polyanhydrides include##STR24##

Included within the scope of the polyanhydrides of the instant inventionare the dianhydrides. The dianhydrides include those represented by theformula ##STR25## wherein: b² is 0 or 1;

b¹ is 0 or 1;

X² is a q² valent aliphatic acyclic hydrocarbon radical or substitutedhydrocarbon radical containing from 2 to about 8 carbon atoms whichtogether with the two carbonyl carbon atoms forms a cyclic structure,where q² is 3 or 4;

X¹ is a q¹ valent aliphatic acyclic hydrocarbon radical or substitutedhydrocarbon radical containing from 2 to about 8 carbon atoms whichtogether with the two carbonyl carbon atoms form a cyclic structure,where q¹ is 3 or 4;

R¹ is a z¹ valent hydrocarbon radical, substituted hydrocarbon radical,hydrocarbon radical containing at least one hetero atom or group, orsubstituted hydrocarbon radical containing at least one hetero atom orgroup, where z¹ =(q² +q¹)-4, with the proviso that if b¹ is zero than q²is 4 and if b¹ is zero than q¹ is 4.

X² and X¹ are preferably alkanetriyls or alkanetetrayls containing from2 to about 8 carbon atoms.

R¹ generally contains from 1 to about 100, preferably 2 to about 50,carbon atoms and may be a divalent, trivalent, or tetravalent, i.e., z¹is an integer having a value of from 2 to 4 inclusive, hydrocarbonradical, substituted hydrocarbon radical, hydrocarbon radical containingat least one hetero atom or group, or substituted hydrocarbon radicalcontaining at least one hetero atom or group. The hydrocarbon radicalsrepresented by R¹ may be aliphatic, either saturated or unsaturated,cycloalphatic, aromatic, or aliphatic-aromatic.

The dianhydrides of Formula VI wherein R is a divalent radical may berepresented by the Formula ##STR26## wherein: R² is a divalenthydrocarbon radical, a substituted divalent hydrocarbon radical, adivalent hydrocarbon radical containing at least one hetero atom orgroup, or a substituted divalent hydrocarbon radical containing at leastone hetero atom or group.

X³ is a trivalent aliphatic acyclic hydrocarbon or substitutedhydrocarbon radical containing from 2 to about 8 carbon atoms whichtogether with the two carbonyl carbon atoms forms a cyclic structure;and

X⁴ is a trivalent aliphatic acyclic hydrocarbon or substitutedhydrocarbon radical containing from 2 to about 8 carbon atoms whichtogether with the two carbonyl carbon atoms forms a cyclic structure.

The divalent hydrocarbon radicals represented by R² contain from 1 toabout 100, preferably 2 to about 50, carbon atoms and include thealkylene, alkenylene, cycloalkylene, cycloalkylidene, arylene,alkarylene and arylalkenylene radicals. The alkylene radicals containfrom 1 to about 100 carbon, and preferably 2 to about 50, may bestraight chain or branched. Typical cycloalkylene and cycloalkylideneradicals are there containing from 4 to about 16 ring carbon atoms. Thecycloalkylene and cyclo-alkylidene radicals may contain substituentgroups, e.g., lower alkyl groups, on one or more ring carbon atoms. Whenmore than one substituent group is present they may be the same ordifferent. Typical arylene radicals are those containing from 6 to 12ring carbons, e.g., phenylene, naphthylene and biphenylene. Typicalalkarylene and aralkylene radicals are those containing from 7 to about50 carbon atoms.

The substituted divalent hydrocarbon radicals represented by R² arethose divalent hydrocarbon radicals defined above which contain at leastone substituent group, typically from 1 to about 5 substituent groups,of the type described hereinafore.

The divalent hydrocarbon radicals containing at least one hetero atom orgroup represented by R¹ are those divalent hydrocarbon radicals definedabove which contain at least one hetero atom or group of the typedefined hereinafore in the carbon chain.

Some illustrative non-limiting examples of dianhydrides of Formula VIainclude ##STR27##

The dianhydrides of Formula VI wherein R¹ is a trivalent radical may herepresented by the formulae ##STR28## wherein: R³ is a trivalenthydrocarbon radical or a trivalent substituted hydrocarbon radical;

X⁵ is a tetravalent aliphatic acyclic hydrocarbon or substitutedhydrocarbon radical containing from 2 to about 8 carbon atoms whichtogether with the carbonyl carbon atoms forms acyclic structure; and

X³ is as defined hereinafore.

The trivalent hydrocarbon radicals represented by R³ in Formulae Vb andVb¹ are trivalent cycloaliphatic or aromatic hydrocarbon radicals. Thetrivalent cycloaliphatic hydrocarbon radicals represented by R³preferably contain from 3 to about 16 ring carbon atoms. The trivalentaromatic hydrocarbon radicals represented by R³ preferably contain from6 to 12 ring carbon atoms. The trivalent substituted hydrocarbonradicals represented by R³ are those trivalent hydrocarbon radicalsdescribed hereinafore which contain at least 1, preferably from 1 toabout 4, substituent groups of the type described hereinafore on thering carbon atoms.

The tetravalent aliphatic acyclic hydrocarbon radicals represented by X⁵Formula Vb are those containing from 1 to about 8 carbon atoms thattogether with the two carbonyl carbon atoms form a cyclic structure.These radicals include the alkanetetrayl radicals. The tetravalentsubstituted aliphatic acylic hydrocarbon radicals represented by X⁵ inFormula VIb are those tetravalent aliphatic acyclic hydrocarbon radicalsdescribed hereinafore which contain at least one substituent group ofthe type described hereinafore.

Some illustrative non-limiting examples of the dianhydrides of FormulaeVIb and VIb¹ include ##STR29##

The dianhydrides of Formula VI wherein R' is a tetravalent radical maybe represented by the formulae ##STR30## wherein: R⁴ is a tetravalenthydrocarbon radical or a tetravalent substituted hydrocarbon radical;

X⁵ is a trivalent aliphatic acyclic hydrocarbon or substitutedhydrocarbon radical containing from 2 to about 8 carbon atoms whichtogether with the carbonyl carbon atoms forms a cyclic structure; and

X⁵ ' is a tetravalent aliphatic a cyclic hydrocarbon or substitutedhydrocarbon radical containing from 2 to about 8 carbon atoms whichtogether with the carbonyl carbon atoms forms a cyclic structure.

The tetravalent hydrocarbon radicals represented by R⁴ in FormulaeVIc--VIc" are tetravalent cycloaliphatic or aromatic hydrocarbonradicals. The tetravalent cycloaliphatic or aromatic hydrocarbonradicals preferably contain from 4 to about 16 ring carbon atoms. Thetetravalent aromatic hydrocarbon radicals preferably contain from 6 to12 ring carbon atoms. The tetravalent substituted hydrocarbon radicalsrepresented by R⁴ are these tetravalent hydrocarbon radicals describedalone which contain at least one substituent group of the type describedhereinafore on at least one carbon atom.

Some illustrative non-limiting examples of the dianhydrides of FormulaeVIc--VIc" include ##STR31##

These polyanhydrides are reacted with the polyamines, polyols or aminoalcohols described hereinafore to produce the intermediate adducts whichare then reacted with the aforedescribed hydrocarbyl substituteddicarboxylic acid producing material or hydrocarbyl substituted hydroxyaromatic material and aldehyde to yield the dispersants of the presentinvention.

The reaction between a polyamine and a polyanhydride to form theintermediate polyanhydride-polyamine adduct is described, for the caseof a dianhydride, in Equation 1 above. In this reaction the differentanhydride moieties in the same polyanhydride molecule react with theprimary amino groups on different polyamine molecules to join or linktogether different polyamine molecules via the polyanhydride molecule.

If a polyanhydride containing more than two dicarboxylic anhydridegroups per molecule, such as a anhydride, is reacted with a polyaminesuch as TEPA then three molecules of polyamine will be joined orconnected together by the polyanhydride. This is illustrated by thefollowing reaction scheme: ##STR32##

If a polyamine containing more than two, e.g., three, primary aminogroups, per molecule is used then one such polyamine molecule may belinked or connected to two other polyamine molecules by threedianhydride molecules. In such case the three primary amino groups oneach polyamine molecule react with anhydride groups on differentpolyanhydride molecules.

The chemistry of the polyanhydride-polyamine reaction is such that theprimary amino functionality in the polyamine is more reactive than thesecondary amino functionality with the anhydride group of thepolyanhydride and therefore the product structure A, i.e., imide,illustrated in Equations 1 and 2 will be the favored product. It is alsopossible, however, that the secondary amino functionality or thehydroxyl functionality of the resulting adduct can react with furthermolecules of the polyanhydride to form a diversity of structures,including structures B and C in Equation 1.

In general the polyanhydride-polyamine intermediate adducts of thepresent invention comprise molecules of polyamines linked to each otherby polyanhydride molecules. For purposes of illustration andexemplification only, and assuming that the polyamine is a polyamine ofFormula I and the polyanhydride is a dianhydride of Formula V, thepolyanhydride-polyamine intermediate adduct contains at least one of thefollowing recurring structural units ##STR33## wherein R, R''', s and tare as defined hereinafore.

The stoichiometry of the polyanhydride and polyamine is one of thefactors that determines the length of the polyanhydride-polyamineadduct, e.g., number of recurring structural units of Formula X.Generally, increasing the concentration in the reaction mixture of thepolyanhydride, up to a point where there is present an equivalent amountof anhydride moieties per primary amino moieties, results in an increasein the length and molecular weight of the intermediate adduct.

Other factors which influence the length and molecular weight of theadduct are reaction times and reaction temperatures. Generally, assuminga fixed amount of polyanhydride in the polyanhydride-polyamine reactionmixture, a higher reaction temperature and/or a longer reaction timeresults in longer or higher molecular weight intermediate adductproduct.

Reaction between the polyanhydride and polyamine is carried out byadding an amount of polyanhydride to the polyamine which is effective tocouple or link at least some of the polyamine molecules. It is readilyapparent to those skilled in the art that the amount of polyanhydrideutilized depends upon a number of factors including (1) the number ofreactive, e.g., primary, amino groups present in the polyamine, (2) thenumber of anhydride groups present in the polyanhydride, (3) and thenumber of polyamine molecules that it is desired to react, i.e., thedegree of coupling or chain length of the polyanhydride-polyamine adductit is desired to achieve.

Generally, however, it is preferred to utilize an amount ofpolyanhydride such that there are present from about 0.01 to 5equivalents of anhydride groups per equivalent of reactive, e.g.,primary, amino groups, preferably from about 0.1 to 2 equivalents ofanhydride groups per equivalent of primary amino group. It is preferred,however, that the polyamine be present in excess in thepolyanhydride-polyamine reaction mixture.

With appropriate variations to provide for the presence of hydroxylgroups the aforedescribed method and discussion for the preparation ofthe polyanhydride-polyamine intermediate adducts is also applicable tothe polyanhydride-polyol and polyanhydride-amino alcohol adducts.

In order to form the dispersants of the present invention the long chainhydrocarbyl substituted dicarboxylic acid material (ii)(a) or the longchain hydrocarbon substituted phenol and an aldehyde (ii)(b) is reactedwith a polyanhydride-polyamine adduct, a polyanhydride-polyol adduct, apolyanhydride-amino alcohol adduct, or a mixture thereof. The amounts ofpolyanhydride adduct and hydrocarbyl substituted dicarboxylic acidmaterial or aldehyde and hydrocarbyl substituted hydroxy aromaticcompound utilized in this reaction are amounts which are effective toform the dispersants of the instant invention, i.e., dispersant formingeffective amounts. It will be apparent to those skilled in the art thatthe amount of polyanhydride adduct utilized will depend, in part, uponthe number of reactive groups (reactive primary amino groups in thepolyanhydride-polyamine adduct, reactive hydroxyl groups in thepolyanhydride-polyol adduct, etc.) present in said polyanhydride adductwhich are available for reaction with, for example, carboxylic acid oranhydride groups of the hydrocarbyl substituted dicarboxylic acidmaterial. Generally, however, the amount of the polyanhydride adduct issuch that sufficient polyanhydride adduct is present to provide fromabout 0.5 to 15, preferably from about 1 to 10, and more preferably fromabout 2 to 4 reactive groups or equivalents, e.g., primary amino groups,for each carboxylic acid or anhydride group or equivalent present in thehydrocarbyl substituted dicarboxylic acid material.

The reaction conditions under which the reaction between thepolyanhydride adduct reactant and the hydrocarbyl substituteddicarboxylic acid material reactant or aldehyde and hydrocarbylsubstituted hydroxy aromatic compound reactants is carried out are thosethat are effective for coreaction between said reactants to occur.Generally, the reaction will proceed at from about 50° to 250° C.,preferably 100° to 210° C. While super-atmospheric pressures are notprecluded, the reaction generally proceeds satisfactorily at atmosphericpressure. The reaction may be conducted using a mineral oil, e.g., 100neutral oil, as a solvent. An inert organic co-solvent, e.g., xylene ortoluene, may also be used. The reaction time generally ranges from about0.25 to 24 hours.

The reaction between the polyanhydride-polyamine adduct and thehydrocarbyl substituted dicarboxylic acid material may be exemplified bythe following reaction scheme which represents the reaction ofpolyisobutenyl succinic anhydride with an alkylenedianhydride/tetraethylene pentamine adduct: ##STR34##

The imide reaction product of this reaction may be represented bystructure A above, while the imide-amide product is represented bystructure B and C above.

Alternately, all of the above polyanhydride adducts may be reacted withlong chain hydrocarbon substituted hydroxy aromatic material and analdehyde (ii)(b). In this embodiment the long chain hydrocarbonsubstituted hydroxy aromatic material and an aldehyde may first beprereacted and this reaction product may then be reacted with thepolyanhydride intermediate adduct. Alternately the polyanhydrideintermediate adduct, long chain hydrocarbon substituted hydroxy aromaticmaterial, and an aldehyde may be reacted substantially simultaneously.In general, the amounts of reactants utilized in these reactions areamounts which are effective to yield the improved dispersants of theinstant invention. Generally these amounts are about a molar proportionof long chain hydrocarbon substituted hydroxy aromatic material such aslong chain hydrocarbon substituted hydroxy aromatic material such aslong chain hydrocarbon substituted phenol, about 1 to about 2.5 moles ofaldehyde such as formaldehyde, and about 0.5 to 2 moles of polyanhydrideadduct. In general, the reactants are admixed and reacted at an elevatedtemperature until the reaction is complete. The reaction may beconducted in the presence of a solvent and in the presence of a quantityof mineral oil.

Further aspects of the present invention reside in the formation ofmetal complexes and other post-treatment derivatives, e.g., boratedderivatives, of the novel additives prepared in accordance with thisinvention. Suitable metal complexes may be formed in accordance withknown techniques of employing a reactive metal ion species during orafter the formation of the present C₅ -C₉ lactone derived dispersantmaterials. Complex-forming metal reactants include the nitrates,thiocyanates, halides, carboxylates, phosphates, thio-phosphates,sulfates, and borates of transition metals such as iron, cobalt, nickel,copper, chromium, manganese, molybdenum, tungsten, ruthenium, palladium,platinum, cadmium, lead, silver, mercury, antimony and the like. Priorart disclosures of these complexing reactions may be found in U.S. Pat.Nos. 3,306,908 and Re. 26,443.

Post-treatment compositions include those formed by reacting the noveladditives of the present invention with one or more post-treatingreagents, usually selected from the group consisting of boron oxide,boron oxide hydrate, boron halides, boron acids, sulfur, sulfurchlorides, phosphorous sulfides and oxides, carboxylic acid or anhydrideacylating agents, anhydrides and episulfides and acrylonitriles. Thereaction of such post-treating agents with the novel additives of thisinvention is carried out using procedures known in the art. For example,boration may be accomplished in accordance with the teachings of U.S.Pat. No. 3,254,025 by treating the additive compound of the presentinvention with a boron oxide, halide, ester or acid. Treatment may becarried out by adding about 1-3 wt. % of the boron compound, preferablyboric acid, and heating and stirring the reaction mixture at about 135°C. to 165° C. for 1 to 5 hours followed by nitrogen stripping andfiltration, if desired. Mineral oil or inert organic solvents facilitatethe process.

The compositions produced in accordance with the present invention havebeen found to be particularly useful as fuel and lubricating oiladditives.

When the compositions of this invention are used in normally liquidpetroleum fuels, such as middle distillates boiling from about 150° to800° F. including kerosene, diesel fuels, home heating fuel oil, jetfuels, etc., a concentration of the additive in the fuel in the range oftypically from 0.001 wt. % to 0.5 wt. %, preferably 0.005 wt. % to 0.2wt. %, based on the total weight of the composition, will usually beemployed. These additives can contribute fuel stability as well asdispersant activity and/or varnish control behavior to the fuel.

The compounds of this invention find their primary utility, however, inlubricating oil compositions, which employ a base oil in which theadditives are dissolved or dispersed. Such base oils may be natural orsynthetic.

Thus, base oils suitable for use in preparing the lubricatingcompositions of the present invention include those conventionallyemployed as crankcase lubricating oils for spark-ignited andcompression-ignited internal combustion engines, such as automobile andtruck engines, marine and railroad diesel engines, and the like.Advantageous results are also achieved by employing the additives of thepresent invention in base oils conventionally employed in and/or adaptedfor use as power transmitting fluids such as automatic transmissionfluids, tractor fluids, universal tractor fluids and hydraulic fluids,heavy duty hydraulic fluids, power steering fluids and the like. Gearlubricants, industrial oils, pump oils and other lubricating oilcompositions can also benefit from the incorporation therein of theadditives of the present invention.

Thus, the additives of the present invention may be suitablyincorporated into synthetic base oils such as alkyl esters ofdicarboxylic acids, polyglycols and alcohols; polyalpha-olefins,polybutenes, alkyl benzenes, organic esters of phosphoric acids,polysilicone oils, etc. selected type of lubricating oil composition canbe included as desired.

The additives of this invention are oil-soluble, dissolvable in oil withthe aid of a suitable solvent, or are stably dispersible materials.Oil-soluble, dissolvable, or stably dispersible as that terminology isused herein does not necessarily indicate that the materials aresoluble, dissolvable, miscible, or capable of being suspended in oil inall proportions. It does mean, however, that the additives, forinstance, are soluble or stably dispersible in oil to an extentsufficient to exert their intended effect in the environment in whichthe oil is employed. Moreover, the additional incorporation of otheradditives may also permit incorporation of higher levels of a particularpolymer adduct hereof, if desired.

Accordingly, while any effective amount of these additives can beincorporated into the fully formulated lubricating oil composition, itis contemplated that such effective amount be sufficient to provide saidlube oil composition with an amount of the additive of typically from0.01 to about 10, e.g., 0.1 to 6.0, and preferably from 0.25 to 3.0 wt.%, based on the weight of said composition.

The additives of the present invention can be incorporated into thelubricating oil in any convenient way. Thus, they can be added directlyto the oil by dispersing, or dissolving the same in the oil at thedesired level of concentration, typically with the aid of a suitablesolvent such as toluene, cyclohexane, or tetrahydrofuran. Such blendingcan occur at room temperature or elevated.

Natural base oils include mineral lubricating oils which may vary widelyas to their crude source, e.g., whether paraffinic, naphthenic, mixed,paraffinicnaphthenic, and the like; as well as to their formation, e.g.,distillation range, straight run or cracked, hydrofined, solventextracted and the like.

More specifically, the natural lubricating oil base stocks which can beused in the compositions of this invention may be straight minerallubricating oil or distillates derived from paraffinic, naphthenic,asphaltic, or mixed base crudes, or, if desired, various blends oils maybe employed as well as residuals, particularly those from whichasphaltic constituents have been removed. The oils may be refined byconventional methods using acid, alkali, and/or clay or other agentssuch as aluminum chloride, or they may be extracted oils produced, forexample, by solvent extraction with solvents of the type of phenol,sulfur dioxide, furfural, dichlorodiethyl ether, nitrobenzene,crotonaldehyde, etc.

The lubricating oil base stock conveniently has a viscosity of typicallyabout 2.5 to about 12, and preferably about 2.5 to about 9 cSt. at 100°C.

Thus, the additives of the present invention can be employed in alubricating oil composition which comprises lubricating oil, typicallyin a major amount, and the additive, typically in a minor amount, whichis effective to impart enhanced dispersancy relative to the absence ofthe additive. Additional conventional additives selected to meet theparticular requirements of a temperatures. In this form the additive perse is thus being utilized as a 100% active ingredient form which can 1added to the oil or fuel formulation by the purchase: Alternatively,these additives may be blended with suitable oil-soluble solvent andbase oil to form concentrate, which may then be blended with alubricating oil base stock to obtain the final formulation Concentrateswill typically contain from about 2 to 80 wt. %, by weight of theadditive, and preferably from about 5 to 40% by weight of the additive.

The lubricating oil base stock for the additive of the present inventiontypically is adapted to perform selected function by the incorporationof additives therein to form lubricating oil compositions (i.e.,formulations).

Representative additives typically present in such formulations includeviscosity modifiers, corrosion inhibitors, oxidation inhibitors,friction modifiers, other dispersants, anti-foaming agents, anti-wearagents, pour point depressants, detergents, rust inhibitors and thelike.

Viscosity modifiers impart high and low temperature operability to thelubricating oil and permit it to remain shear stable at elevatedtemperatures and also exhibit acceptable viscosity or fluidity at lowtemperatures. These viscosity modifiers are generally high molecularweight hydrocarbon polymers including polyesters. The viscositymodifiers may also be derivatized to include other properties orfunctions, such as the addition of dispersancy properties.

These oil soluble viscosity modifying polymers will generally haveweight average molecular weights of from about 10,000 to 1,000,000,preferably 20,000 to 500,000, as determined by gel permeationchromatography or light scattering methods.

Representative examples of suitable viscosity modifiers are any of thetypes known to the art including polyisobutylene, copolymers of ethyleneand propylene, polymethacrylates, methacrylate copolymers, copolymers ofan unsaturated dicarboxylic acid and vinyl compound, interpolymers ofstyrene and acrylic esters, and partially hydrogenated copolymers ofstyrene/isoprene, styrene/butadiene, and isoprene/butadiene, as well asthe partially hydrogenated homopolymers of butadiene and isoprene.

Corrosion inhibitors, also known as anti-corrosive agents, reduce thedegradation of the metallic parts contacted by the lubricating oilcomposition. Illustrative of corrosion inhibitors are phosphosulfurizedhydrocarbons and the products obtained by reaction of aphosphosulfurized hydrocarbon with an alkaline earth metal oxide orhydroxide, preferably in the presence of an alkylated phenol or of analkylphenol thioester, and also preferably in the presence of analkylated phenol or of an alkylphenol thioester, and also preferably inthe presence of carbon dioxide. Phosphosulfurized hydrocarbons areprepared by reacting a suitable hydrocarbon such as a terpene, a heavypetroleum fraction of a C₂ to C₆ olefin polymer such as polyisobutylene,with from 5 to 30 wt. % of a sulfide of phosphorus for 1/2 to 15 hours,at temperature in the range of about 66° to about 316° C. Neutralizationof the phosphosulfurized hydrocarbon may be effected in the mannertaught in U.S Pat. No. 1,969,324.

Oxidation inhibitors, or antioxidants, reduce the tendency of mineraloils to deteriorate in service which deterioration can be evidenced bythe products of oxidation such as sludge and varnish-like deposits onthe metal surfaces, and by viscosity growth. Such oxidation inhibitorsinclude alkaline earth metal salts of alkylphenolthioesters havingpreferably C₅ to C₁₂ alkyl side chains, e.g., calcium nonylphenolsulfide, barium toctylphenyl sulfide, dioctylphenylamine,phenylalphanaphthylamine, phospho-sulfurized or sulfurized hydrocarbons,etc.

Other oxidation inhibitors or antioxidants useful in this inventioncomprise oil-soluble copper compounds. The copper may be blended intothe oil as any suitable oilsoluble copper compound. By oil soluble it ismeant that the compound is oil soluble under normal blending conditionsin the oil or additive package. The copper compound may be in thecuprous or cupric form. The copper may be in the form of the copperdihydrocarbyl thio- or dithio-phosphates. Alternatively, the copper maybe added as the copper salt of a synthetic or natural carboxylic acid.Examples of same thus include C₁₀ to C₁₈ fatty acids, such as stearic orpalmitic acid, but unsaturated acids such as oleic or branchedcarboxylic acids such as napthenic acids of molecular weights of fromabout 200 to 500, or synthetic carboxylic acids, are preferred, becauseof the improved handling and solubility properties of the resultingcopper carboxylates. Also useful are oil-soluble copper dithiocarbamatesof the general formula (R²⁰ R²¹,NCSS)zCu (where z is 1 or 2, and R²⁰ andR²¹, are the same or different hydrocarbyl radicals containing from 1 to18, and preferably 2 to 12, carbon atoms, and including radicals such asalkyl, alkenyl, aryl, aralkyl, alkaryl and cycloaliphatic radicals.Particularly preferred as R²⁰ and R²¹, groups are alkyl groups of from 2to 8 carbon atoms. Thus, the radicals may, for example, be ethyl,n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, amyl, n-hexyl, i-hexyl,n-heptyl, n-octyl, decyl, dodecyl, octadecyl, 2-ethylhexyl, phenyl,butylphenyl, cyclohexyl, methylcyclopentyl, propenyl, butenyl, etc. Inorder to obtain oil solubility, the total number of carbon atoms (i.e.,R²⁰ and R²¹,) will generally be about 5 or greater. Copper sulphonates,phenates, and acetylacetonates may also be used.

Exemplary of useful copper compounds are copper Cu^(I) and/or Cu^(II)salts of alkenyl succinic acids or anhydrides. The salts themselves maybe basic, neutral or acidic. They may be formed by reacting (a)polyalkylene succinimides (having polymer groups of M_(n) of 700 to5,000) derived from polyalkylene-polyamines, which have at least onefree carboxylic acid group, with (b) a reactive metal compound. Suitablereactive metal compounds include those such as cupric or cuproushydroxides, oxides, acetates, borates, and carbonates or basic coppercarbonate.

Examples of these metal salts are Cu salts of polyisobutenyl succinicanhydride, and Cu salts of polyisobutenyl succinic acid. Preferably, theselected metal employed is its divalent form, e.g., Cu+2. The preferredsubstrates are polyalkenyl succinic acids in which the alkenyl group hasa molecular weight greater than about 700. The alkenyl group desirablyhas a M_(n) from about 900 to 1,400, and up to 2,500, with a M_(n) ofabout 950 being most preferred. Especially preferred is polyisobutylenesuccinic anhydride or acid. These materials may desirably be dissolvedin a solvent, such as a mineral oil, and heated in the presence of awater solution (or slurry) of the metal bearing material. Heating maytake place between 70° C. and about 200° C. Temperatures of 100° C. to140° C. are entirely adequate. It may be necessary, depending upon thesalt produced, not to allow the reaction to remain at a temperatureabove about 140° C. for an extended period of time, e.g., longer than 5hours, or decomposition of the salt may occur.

The copper antioxidants (e.g., Cu-polyisobutenyl succinic anhydride,Cu-oleate, or mixtures thereof) will be generally employed in an amountof from about 50 to 500 ppm by weight of the metal, in the finallubricating or fuel composition.

Friction modifiers serve to impart the proper friction characteristicsto lubricating oil compositions such as automatic transmission fluids.

Representative examples of suitable friction modifiers are found in U.S.Pat. No. 3,933,659 which discloses fatty acid esters and amides; U.S.Pat. No. 4,176,074 which describes molybdenum complexes ofpolyisobutyenyl succinic anhydride-amino alkanols; U.S. Pat. No.4,105,571 which discloses glycerol esters of dimerized fatty acids; U SPat. No. 3,779,928 which discloses alkane phosphonic acid salts; U.S.Pat. No. 3,778,375 which discloses reaction products of a phosphonatewith an oleamide; U.S. Pat. No. 3,852,205 which disclosesS-carboxyalkylene hydrocarbyl succinimide, S-carboxyalkylene hydrocarbylsuccinamic acid and mixtures thereof; U.S. Pat. No. 3,879,306 whichdiscloses N(hydroxyalkyl)alkenylsuccinamic acids or succinimides: U.S.Pat. No. 3,932,290 which discloses reaction products of di- (loweralkyl) phosphites and anhydrides; and U.S. Pat. No. 4,028,258 whichdiscloses the alkylene oxide adduct of phosphosulfurizedN-(hydroxyalkyl) alkenyl succinimides. The disclosures of the abovereferences are herein incorporated by reference. The most preferredfriction modifiers are succinate esters, or metal salts thereof, ofhydrocarbyl substituted succinic acids or anhydrides andthiobis-alkanols such as described in U.S. Pat. No. 4,344,853.

Dispersants maintain oil insolubles, resulting from oxidation duringuse, in suspension in the fluid thus preventing sludge flocculation andprecipitation or deposition on metal parts. Suitable dispersants includehigh molecular weight alkyl succinimides, the reaction product ofoil-soluble polyisobutylene succinic anhydride with ethylene amines suchas tetraethylene pentamine and borated salts thereof.

Pour point depressants, otherwise known as lube oil flow improvers,lower the temperature at which the fluid will flow or can be poured.Such additives are well known. Typically of those additives whichusefully optimize the low temperature fluidity of the fluid are C8-C18dialkylfumarate vinyl acetate copolymers, polymethacrylates, and waxnaphthalene. Foam control can be provided by an antifoamant of thepolysiloxane type, e.g., silicone oil and polydimethyl siloxane.

Anti-wear agents, as their name implies, reduce wear of metal parts.Representatives of conventional antiwear agents are zincdialkyldithiophosphate and zinc diaryldithiosphate.

Detergents and metal rust inhibitors include the metal salts ofsulphonic acids, alkyl phenols, sulfurized alkyl phenols, alkylsalicylates, naphthenates and other oil soluble mono- and di-carboxylicacids. Highly basic (viz. overbased) metal sales, such as highly basicalkaline earth metal sulfonates (especially Ca and Mg salts) arefrequently used as detergents. Representative examples of suchmaterials, and their methods of preparation, are found in co-pendingSer. No. 754,001, filed Jul. 11, 1985, the disclosure of which is herebyincorporated by reference.

Some of these numerous additives can provide a multiplicity of effects,e.g., a dispersant-oxidation inhibitor. This approach is well known andneed not be further elaborated herein.

Compositions when containing these conventional additives are typicallyblended into the base oil in amounts which are effective to providetheir normal attendant function. Representative effective amounts ofsuch additives are illustrated as follows:

    ______________________________________                                                          Wt. % a.i.                                                                              Wt. % a.i.                                        Additive          (Broad)   (Preferred)                                       ______________________________________                                        Viscosity Modifier                                                                               .01-12   .01-4                                             Corrosion Inhibitor                                                                             .01-5     .01-1.5                                           Oxidation Inhibitor                                                                             .01-5     .01-1.5                                           Dispersant         .1-20    .1-8                                              Pour Point Depressant                                                                           .01-5     .01-1.5                                           Anti-Foaming Agents                                                                             .001-3    .001-0.15                                         Anti-Wear Agents  .001-5    .001-1.5                                          Friction Modifiers                                                                              .01-5     .01-1.5                                           Detergents/Rust Inhibitors                                                                       .01-10   .01-3                                             Mineral Oil Base  Balance   Balance                                           ______________________________________                                    

When other additives are employed it may be desirable, although notnecessary, to prepare additive concentrates comprising concentratedsolutions or dispersions of the dispersant (in concentrate amountshereinabove described), together with one or more of said otheradditives (said concentrate when constituting an additive mixture beingreferred to herein as an additive package) whereby several additives canbe added simultaneously to the base oil to form the lubricating oilcomposition. Dissolution of the additive concentrate into thelubricating oil may be facilitated by solvents and by mixing accompaniedwith mild heating, but this is not essential. The concentrate oradditive-package will typically be formulated to contain the dispersantadditive and optional additional additives in proper amounts to providethe desired concentration in the final formulation when theadditive-package is combined with a predetermined amount of baselubricant. Thus, the products of the present invention can be added tosmall amounts of base oil or other compatible solvents along with otherdesirable additives to form additive-packages containing activeingredients in collective amounts of typically from about 2.5 to about90%, and preferably from about 5 to about 75%, and most preferably fromabout 8 to about 50% by weight additives in the appropriate proportionswith the remainder being base oil.

The final formulations may employ typically about 10 wt. % of theadditive-package with the remainder being base oil.

All of said weight percents expressed herein are based on activeingredient (a.i.) content of the additive, and/or upon the total weightof any additive-package, or formulation which will be the sum of thea.i. weight of each additive plus the weight of total oil or diluent.

This invention will be further understood by reference to the followingexample, wherein all parts are parts by weight and all molecular weightsare number weight average molecular weights as noted, and which includepreferred embodiments of the invention.

The following example illustrates a dispersant falling outside the scopeof the instant invention in that no polyanhydride is utilized in thepreparation of this dispersant. This example is presented forcomparative purposes only.

COMPARATIVE EXAMPLE 1

Into a reactor vessel are charged, under a nitrogen blanket, 134 gramsof S150N mineral oil, 4.7 grams (0.05 mole) of tetraethylene pentamineand 197.84 grams (0.1 mole) of polyisobutylene succinic anhydride(reaction product of maleic anhydride and polyisobutylene having a M_(n)of about 2,225, said reaction product having a polyisobutylene tosuccinic anhydride ratio of about 1:1.1). The resultant reaction mixtureis heated at 150° C. and sparged with nitrogen for 3 hours. The oilsolution containing the product is filtered and the resultant filteredsolution of the product has a viscosity at 100° C. of 408 centistokes.

The following example illustrate a dispersant of the instant invention.

EXAMPLE 2

Into a reactor vessel are, charged under a nitrogen blanket, 140 gramsof S150N mineral oil, 100 cc of toluene, 20 cc of isopropanol 5.4 grams(0.025 mole) of paramellitic dianhydride, and 4.7 grams (0.05 mole) oftetraethylene pentamine. This reaction mixture is heated at 120° C. forone hour. At the end of this one-hour period 197.8 grams (0.1 mole) ofpolyisobutylene succinic anhydride of the type used in ComparativeExample 1 are introduced into the reactor vessel and the resultantreaction mixture is heated at 150° C. for 3 hours while sparging withnitrogen. the solution containing the product is filtered and theresultant filtered solution of the product has a viscosity at 100° C. of750 centistokes.

As can be seen the viscosity of the oil solution of the dispersant ofthe instant invention (Example 2) is higher than that of the oilsolution of conventional dispersant of Comparative Example 1.

What is claimed is:
 1. An oil soluble composition useful as dispersantadditive in lubrication oils consisting essentially of reaction productof:(i) a dispersant-imparting effective amount of at least oneintermediate adduct consisting essentially of reaction product of(a) atleast one polyanhydride reactant, and (b) at least one polyaminereactant wherein the polyamine reactant contains at least two reactiveamino groups, at least one of which is a primary amino group, whereinthe amount of polyanhydride reactant utilized is such that there arepresent about 0.01 to about 10 equivalents of anhydride groups perequivalent of primary amino group, and wherein said intermediate adductcomprises within its structure a moiety comprising the residue of atleast two polyanhydride molecules linked together by the reside of apolyamine molecule, reacted with; (ii) at least one long chainhydrocarbyl substituted C₄ -C₁₀ dicarboxylic acid or anhydride, whereinsaid long chain hydrocarbyl has a number average molecular weight offrom about 500 to about 6,000, and wherein the amount of adduct presentis sufficient to provide from about 0.5 to about 15 reactive aminogroups for each carboxylic acid or anhydride group present on thehydrocarbyl substituted dicarboxylic acid or anhydride.
 2. Thecomposition of claim 1 wherein said long chain hydrocarbyl substitutedC₄ -C₁₀ dicarboxylic acid or anhydride (ii) is comprised of reactionproduct of olefin polymer of a C₂ -C₁₈ monoolefin, said olefin polymerhaving a number average molecular weight of about 500 to about 6,000,and a C₄ -C₁₀ monounsaturated dicarboxylic acid or anhydride.
 3. Thecomposition of claim 2 wherein said olefin polymer is polyisobutylene.4. The composition of claim 3 wherein said monounsaturated dicarboxylicacid or anhydride is maleic anhydride.
 5. The composition of claim 4wherein the number average molecular weight of said polyisobutylene isfrom about 850 to about 1,000.
 6. The composition of claim 1 whereinsaid polyamine reactant contains at least one primary amino group and atleast one secondary amino group.
 7. The composition of claim 1 whereinsaid polyamine reactant is an aliphatic saturated amine represented bythe formula ##STR35## wherein: R^(IV), R' and R''' are independentlyselected from the group consisting of hydrogen, C₁ to C₂₅ straight orbranched chain alkyl radicals, C₁ to C₁₂ alkoxy C₂ to C₆ alkyleneradicals, and C₂ to C₁₂ alkylamino C₂ to C₆ alkylene radicals;each s isindependently selected from integers having a value of from 2 to 6; andt is a number of 0 to 10, with the proviso that R^(IV), R' and R''' areselected such that said polyamine reactant always contains at least tworeactive amino groups, at least one of which is a primary amino group.8. The composition of claim 1 wherein said polyamine is selected fromthe group consisting of 1,2-diaminoethane, 1,3-diaminopropane,1,4-diaminobutane, diethylene triamine, N,N-di-(2-aminoethyl)ethylenediamine, and N-dodecyl-1,3-propane diamine.
 9. The composition of claim1 wherein said polyamine is a polyoxyalklene polyamine.
 10. Aconcentrate comprising about 10% to about 97.5% of a lubricating oil andabout 2.5% to about 90% of the dispersant additive of claim
 1. 11. Thecomposition of claim 1 wherein said polyanhydride reactant isrepresented by the formula ##STR36## wherein: b is 0 or 1;w is thenumber of ##STR37## groups present on R, and is at least 2; X is a qvalent aliphatic acyclic hydrocarbon or substituted hydrocarbon radicalcontaining from 2 to about 8 carbon atoms which together with the twocarbonyl carbon atoms forms a cyclic structure, where q is 3 or 4; and Ris a z valent hydrocarbon radical, substituted hydrocarbon radical,hydrocarbon radical containing at least one hetero atom or group, orsubstituted hydrocarbon radical containing at least one hetero atom orgroup, wherein z=(q-2)w with the proviso that if b=0 then q=4.
 12. Thecomposition of claim 11 wherein w is from 2 to about
 10. 13. Thecomposition of claim 12 wherein b is one.
 14. The composition of claim12 wherein w is two.
 15. A lubricating oil composition comprising:(A) amajor amount of lubricating oil; and (B) a minor amount of an oilsoluble dispersant consisting essentially of reaction product of(i) atleast one intermediate adduct consisting essentially of reaction productof(a) a dispersant-imparting effective amount of at least onepolyanhydride reactant, and (b) at least one polyamine reactant, whereinthe polyamine reactant contains at least two reactive amino groups atleast one of which is a primary amino group, wherein the amount ofpolyanhydride reactant utilized is such that there are present about0.01 to about 10 equivalents of anhydride groups per equivalent ofprimary amino group, and wherein said intermediate adduct compriseswithin its structure a moiety comprising at least two polyanhydridemolecules linked together by the residue of a polyamine molecule,reacted with (ii) at least one long chain hydrocarbyl substituted C₄-C₁₀ dicarboxylic acid or anhydride, wherein said long chain hydrocarbylhas a number average molecular weight of from about 500 to about 6,000,and wherein the amount of adduct present is sufficient to provide about0.5 to about 15 reactive amino groups for each hydrocarbyl substitutedcarboxylic acid or anhydride.
 16. The composition of claim 15 whereinsaid polyamine contains at least one secondary amino group.
 17. Thecomposition of claim 15 wherein said polyamine is a polyoxyalkylenepolyamine.
 18. The composition of claim 15 wherein said long chainhydrocarbyl substituted C₄ -C₁₀ dicarboxylic acid or anhydride (B)(ii)is comprised of reaction product of olefin polymer of a C₂ -C₁₈monoolefin, said olefin polymer having a number average molecular weightof about 500 to about 6,000, and a C₄ -C₁₀ monounsaturated dicarboxylicacid, wherein there are an average of about 0.7 to about 2.0dicarboxylic acid producing moieties per molecule of said olefin polymeror anhydride.
 19. The composition of claim 18 wherein said olefinpolymer is polyisobutylene.
 20. The composition of claim 19 wherein saidmonounsaturated dicarboxylic acid or anhydride is maleic anhydride. 21.The composition of claim 20 wherein the number average molecular weightof said polyisobutylene is from about 800 to about 2,500.
 22. Thecomposition of claim 15 wherein said polyamine reactant is an aliphaticsaturated amine represented by the formula ##STR38## wherein: R^(IV), R'and R''' are independently selected from the group consisting ofhydrogen, C₁ to C₂₅ straight or branched chain alkyl radicals, C₁ to C₁₂alkoxy C₂ to C₆ alkylene radicals, and C₂ to C₁₂ alkylamino C₂ to C₆alkylene radicals;each s is independently selected from integers havinga value of from 2 to 6; and t is a number of 0 to 10, with the provisothat R^(IV), R' and R''' are selected such that said polyamine reactantalways contains at least two reactive amino groups, at least one ofwhich is a primary amino group.
 23. The composition of claim 22 whereinsaid polyamine reactant is selected from the group consisting of1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, diethylenetriamine, triethylene tetramine, tetraethylene pentamine,di-(1,3-propylene)triamine, N,N-di-(2-aminoethyl)ethylene diamine, andN-dodecyl-1,3propane diamine.
 24. The composition of claim 15 whereinsaid polyanhydride reactant is represented by the formula ##STR39##wherein: b is 0 or 1;w is the number of ##STR40## groups present on R,and is at least 2; X is a q valent aliphatic acyclic hydrocarbon orsubstituted hydrocarbon radical containing from 2 to about 8 carbonatoms which together with the two carbonyl carbon atoms forms a cyclicstructure, where q is 3 or 4; and R is a z valent hydrocarbon radical,substituted hydrocarbon radical, hydrocarbon radical containing at leastone hetero atom or group, or substituted hydrocarbon radical containingat least one hetero atom or group, where z=(q-2)w with the proviso thatif b=0 then q=4.
 25. The composition of claim 24 wherein w is from 2 toabout
 10. 26. The composition of claim 25 wherein b is one.
 27. Thecomposition of claim 26 wherein w is two.
 28. A process for preparing apolyanhydride adduct material useful as a lubricating oil additivecomprising:(i) reacting a dispersant-imparting effective amount of atleast one polyanhydride reactant with at least one polyamine to reactantform a polyanhydride intermediate adduct having within its structure theresidue of at least two polyanhydride molecules linked together by theresidue of a polyamine molecule, wherein the polyamine reactant containsat least two reactive amino groups at least one of which is a primaryamino group and wherein the amount of polyanhydride reactant utilized issuch that there are present about 0.01 to about 10 equivalents ofanhydride groups per equivalent of primary amino group; and (ii)reacting said polyanhydride intermediate adduct with at least onehydrocarbyl substituted acid or anhydride being formed by reacting anolefin polymer of a C₂ -C₁₈ monoolefin, said olefin polymer having anumber average molecular weight of about 500 to about 6,000, and a C₄-C₁₀ monounsaturated dicarboxylic acid or anhydride, wherein the amountof adduct present is sufficient to provide about 0.5 to about 15reactive amino groups for each hydrocarbyl substituted carboxylic acidor anhydride.
 29. The process of claim 28 wherein the polyamine reactantis used such that the total number of reactive amino groups in thereaction mixture is in stoichiometric excess relative to the totalnumber of anhydride moieties in the polyanhydride reactant present inthe reaction mixture.
 30. The process of claim 28 wherein said C₄ -C₁₀monounsaturated dicarboxylic acid or anhydride is maleic anhydride. 31.The process of claim 30 wherein said olefin polymer comprisespolyisobutylene, wherein there are about 1 to about 1.5 succinicanhydride units per polyisobutylene moiety present in said hydrocarbylsubstituted C₄ -C₁₀ dicarboxylic acid or anhydride, and wherein thenumber average molecular weight of said polyisobutylene is from about800 to about
 2500. 32. The process of claim 30 wherein said polyaminereactant is an aliphatic saturated amine having the formula: ##STR41##wherein R^(IV), R' and R''' are independently selected from the groupconsisting of hydrogen, C₁ to C₂₅ straight or branched chain alkylradicals, C₁ to C₁₂ alkoxy C₂ to C₆ alkylene radicals, and C₂ to C₁₂alkylamino C₂ to C₆ alkylene radicals; each s is independently selectedfrom integers having a value of from 2 to 6; and t is a number of 0 to10, with the proviso that R^(IV), R' and R''' are selected such thatsaid polyamine reactant always contains at least two reactive aminogroups, at least one of which is a primary amino group.
 33. The processof claim 32, wherein said amine polyamine reactant is selected from thegroup consisting of 1,2-diaminoethane, 1,3-diaminopropane,1,4-diaminobutane, 6-diaminopropane, diethylene triamine, triethylenetetramine, tetraethylene pentamine, di-(1,3-propylene) triamine,N,N-di-(2-aminoethyl) ethylene diamine, and N dodecyl-1,3-propanediamine.
 34. The process of claim 28 wherein said polyamine reactant hasfrom 2 to about 60 total carbon atoms and from about 2 to about 12nitrogen atoms.
 35. The process of claim 34 wherein said polyaminereactant is a polyoxyalkylene polyamine.
 36. The process of claim 28wherein the polyanhydride reactant is used in an amount sufficient toprovide from about 0.1 to about 5 equivalents of anhydride moieties perone reactive amino moiety, said reactive amino moiety being selectedfrom the group consisting of primary and secondary amino moieties. 37.The process of claim 36 wherein the polyanhydride reactant is used in anamount sufficient to provide from about 0.1 to about 2 equivalents ofanhydride moieties per one reactive amino moiety.
 38. The process ofclaim 25 wherein said polyanhydride reactant is represented by theformula ##STR42## wherein: b is 0 or 1;w is the number of ##STR43##groups present on R, and is at least 2; X is a q valent aliphaticacyclic hydrocarbon or substituted hydrocarbon radical containing from 2to about 8 carbon atoms which together with the two carbonyl carbonatoms forms a cyclic structure, where q is 3 or 4; and R is a z valenthydrocarbon radical, substituted hydrocarbon radical, hydrocarbonradical containing at least one hetero atom or group, or substitutedhydrocarbon radical containing at least one hetero atom or group, wherez=(q-2)w with the proviso that if b=0 then q=4.
 39. The process of claim38 wherein w is from 2 to about
 10. 40. The process of claim 39 whereinb is one.
 41. The process of claim 40 wherein w is two.